1. Field of the Invention
The invention relates to a remote control system in which a plurality of controllers control the values of parameters of a controlled device connected thereto via a network. The invention relates also to a communication system in which a plurality of varying data is transmitted from a first node to a plurality of second node.
2. Description of the Related Art
Conventionally, as an example of a communication system in which a plurality of varying data is transmitted from a first node to a plurality of second node, a remote control system has been known in which audio signal processors such as an amplifier and the like and a controller such as a PC (personal computer) or the like are connected via a network so that the user can control the values of parameters in the audio signal processors by operating the controller. Generally, the Ethernet (registered trademark) which has become most popular is used as the network.
It is also known that the control of the values of the parameters in such a remote control system is performed in the following procedure. Specifically, the controller which receives an instruction to change the value of a parameter from the user transmits a change command requesting to change the value of the parameter to the audio signal processor (a controlled device) being a controlled object. The audio signal processor which receives the change command then changes the data in its current memory according to the request. The audio signal processor then notifies the controller of the change result, and the controller confirms that the change has been properly performed based on the change result.
In this event, even in the case where there are a plurality of controllers, if the system is configured such that the audio signal processor notifies all of the controllers controlling the audio signal processor of the change result, not only the controller which issued the change command but also the other controllers can grasp the change result of the value of the parameter in the audio signal processor and display the new value of the parameter and so on.
Such a remote control system is described, for example, in Documents 1 and 2.    Document 1: Japanese unexamined patent publication No. 2009-218937    Document 2: Japanese unexamined patent publication No. 2009-218947